% Layout scheme for outer elements: split header and footer
\useoutertheme{split}

% Color scheme for outer elements: use background colors
\usecolortheme{whale}

% Layout scheme for inner elements: rounded elements
\useinnertheme{rounded}

% Color scheme for inner elements: use foreground colors
\usecolortheme{rose}

% Itemize items: default (triangle), circle, square, ball
\setbeamertemplate{itemize items}[circle]

% Enumerate items: default, circle, square, ball
\setbeamertemplate{enumerate items}[circle]

% Outline: default, sections numbered, subsections numbered, circle, square, ball, ball unnumbered
\setbeamertemplate{sections/subsections in toc}[default]

% General blocks:
\setbeamertemplate{blocks}[rounded][shadow=true]

% Title page:
\setbeamertemplate{title page}[default][colsep=-4bp,rounded=true]

% Part page:
\setbeamertemplate{part page}[default][colsep=-4bp,rounded=true]

% Background
\pgfdeclareimage[width=\paperwidth,height=0.95\paperheight]{bg}{yzu_background}
\setbeamertemplate{background}{\pgfuseimage{bg}}

% Colors
\usecolortheme[RGB={143,23,24}]{structure}

\setbeamercolor{frametitle}{parent=subsection in head/foot}
\setbeamercolor{frametitle right}{parent=subsection in head/foot}


\pgfdeclarehorizontalshading[frametitle.bg,frametitle right.bg]{beamer@frametitleshade}{\paperheight}{%
  color(0pt)=(frametitle.bg);
  color(\paperwidth)=(frametitle right.bg)}

\AtBeginDocument{
  \pgfdeclareverticalshading{beamer@topshade}{\paperwidth}{%
    color(0pt)=(bg);
    color(4pt)=(black!50!bg)}
}
% footline: author | title | date | framenumber

\defbeamertemplate*{footline}{yzu theme}{%
  \leavevmode%
  \hbox{%
  \begin{beamercolorbox}[wd=.2\paperwidth,ht=2.25ex,dp=1ex,center]{title in head/foot}%
    \usebeamerfont{author in head/foot}\insertshortauthor
  \end{beamercolorbox}%
  \begin{beamercolorbox}[wd=.25\paperwidth,ht=2.25ex,dp=1ex,center]{title in head/foot}%
    \usebeamerfont{author in head/foot}\insertshortdate
  \end{beamercolorbox}%
  \begin{beamercolorbox}[wd=.485\paperwidth,ht=2.25ex,dp=1ex,center]{title in head/foot}%
   \usebeamerfont{author in head/foot}{扬州大学信息工程学院（人工智能学院）}
  \end{beamercolorbox}%
   \begin{beamercolorbox}[wd=0.065\paperwidth,ht=2.25ex,dp=1ex,right]{title in head/foot}%
    \insertframenumber{} / \inserttotalframenumber\hspace*{2ex}
  \end{beamercolorbox}}%
  \vskip0pt%
}

\defbeamertemplate*{headline}{yzu theme}{%
  \leavevmode%
  \@tempdimb=6.4375ex%
    \pgfdeclareimage[height=.95\@tempdimb]{logo}{njulogo.pdf}%
    \pgfdeclareimage[height=1.\@tempdimb]{title_logo}{logo.png}%
    \pgfdeclareimage[height=1.\@tempdimb]{math_logo}{xxgc_name.png}%
  \logo{\pgfuseimage{logo}}%
  \ifdim\@tempdimb>0pt%
    \advance\@tempdimb by 1.125ex%
     \begin{beamercolorbox}[wd=.15\paperwidth,ht=\@tempdimb,center]{subsection in head/foot}%
      \vbox to\@tempdimb{\vfil\vfil\vfil}
      %\vbox to\@tempdimb{\vfil\pgfuseimage{math_logo}\vfil}%
    \end{beamercolorbox}%
    \begin{beamercolorbox}[wd=.7\paperwidth,ht=\@tempdimb]{subsection in head/foot}%
      \vbox to\@tempdimb{\vfil\insertsectionnavigationhorizontal{.5\textwidth}{\hskip0pt 
      plus1filll}{}\vfil}
    \end{beamercolorbox}%
    \begin{beamercolorbox}[wd=.15\paperwidth,ht=\@tempdimb,center]{subsection in head/foot}%
      \vbox to\@tempdimb{\vfil\pgfuseimage{title_logo}\vfil}%
    \end{beamercolorbox}%
    %\begin{beamercolorbox}[wd=.065\paperwidth,ht=\@tempdimb,center]{subsection in head/foot}%
      %\vbox to\@tempdimb{\vfil\vfil\vfil\vfil}
      %\vbox to\@tempdimb{\vfil\insertlogo\vfil\vfil}%
    %\end{beamercolorbox}%
  \fi%
}

\defbeamertemplate*{frametitle}{yzu theme}{%
  \nointerlineskip%
  \hbox{\leavevmode
    \advance\beamer@leftmargin by -12bp%
    \advance\beamer@rightmargin by -12bp %
    \beamer@tempdim=\textwidth%
    \advance\beamer@tempdim by \beamer@leftmargin%
    \advance\beamer@tempdim by \beamer@rightmargin%
    \hskip-\Gm@lmargin\hbox{%
      \setbox\beamer@tempbox=\hbox{\begin{minipage}[b]{\paperwidth}%
          \vbox{}\vskip-.75ex%
          \leftskip0.3cm%
          \rightskip= 0pt plus1fil \leavevmode
          \insertframetitle%
          \ifx\insertframesubtitle\@empty%
            \strut\par%
          \else
            \par{\usebeamerfont*{framesubtitle}{\usebeamercolor[bg]{framesubtitle}\insertframesubtitle}\strut\par}%
          \fi%
          \nointerlineskip
          \vbox{}%
          \end{minipage}}%
      \beamer@tempdim=\ht\beamer@tempbox%
      \advance\beamer@tempdim by 2pt%
      \begin{pgfpicture}{0mm}{0pt}{\paperwidth}{\beamer@tempdim}
        \usebeamercolor{frametitle right}
        \pgfpathrectangle{\pgfpointorigin}{\pgfpoint{\paperwidth}{\beamer@tempdim}}
        \pgfusepath{clip}
        \pgftext[left,base]{\pgfuseshading{beamer@frametitleshade}}
      \end{pgfpicture}
      \hskip-\paperwidth%
      \box\beamer@tempbox%
    }%
    \hskip-\Gm@rmargin%
  }%
}
